The bottom line is that Daesh's defeat requires not just hammering them on the battlefield but, simultaneously, revived political reconciliation with Sunnis.
I've been in a position before where a president has turned to me in the Oval Office in a difficult moment, without any pleasantries, and said, 'I'm asking you as your president and Commander in Chief to take command of the international security force in Afghanistan.' The only response can be, 'Yes, Mr. President.'
No greater privilege than I had as a soldier and then as a spymaster and to some degree now in the business world.
The president and I sat down in the Oval Office, and he expressed very clearly that what he wants from me is my best professional military advice.
The word 'insurgency' had connotations that really sent a shiver down the spine of folks in Washington, in the United States - for good reason, because it means this is something much bigger than just a few terrorist cells.
There is nothing I can do to undo what I did. I can only say again how sorry I am to those I let down and then strive to go forward with a greater sense of humility and purpose, and with gratitude to those who stood with me during a very difficult chapter in my life.
But clearly, this is what this is about. It's about pushing the security bubble out. It's about rooting out every last guy, so that there's not even somebody who can fire a single, solitary RPG round from some little qalat out here.
Partners from the Islamic world are of particular importance. Indeed, they have huge incentives to be involved, as the ongoing struggles are generally not clashes between civilizations. Rather, what we are seeing is more accurately a clash within a civilization: that of the Islamic world.
Even before the missteps that I've had, I was never going to run for office. My family is adamantly opposed to it, and frankly, my politics don't necessarily work for the primaries of either of our parties.
This is actually true of the overall fight against al-Qaeda and trans-national extremists, that as you put pressure on them in one location, they'll seek safe haven sanctuaries in other areas. So you do have to continue to pursue them. But they have less capability.
When I was commander of Central Command, obviously we were very concerned about the developments in Yemen, the developments in Somalia and elsewhere, in Africa and so forth. But the al Qaeda senior leadership is under unprecedented pressure.
The situation in Iraq was dire at the end of 2006, when President George W. Bush decided to implement the surge and selected me to command it. Indeed, when I returned to Baghdad in early February 2007, I found the conditions there to be even worse than I had expected.
The biggest of the big ideas that guided the strategy during the surge was explicit recognition that the most important terrain in the campaign in Iraq was the human terrain - the people - and our most important mission was to improve their security.
Obviously, resilience matters. I was no stranger to adversity, but it's different when it's personal. Not something I would recommend.
If you're asked, you've got to serve - put aside any reservations based on campaign rhetoric... and figure out what's best for the country.